Ok I would like to suggest you to go through the below steps and after that let me know if it helps you out:
First of all open start menu and after that type: REGEDIT in search bar and then click on ok button. Now on the result double click on windows registry editor and under that go to the below registry key:
Now if you cannot find the StorageDevicePolicies key then you should create StorageDevicePolicies manually. For that create new DWORD (32 bit) and then type name as WriteProtect. Now double click on WriteProtect and after that set the value to 0 (zero). Once you have done that save the setting and reboot the system to take effect.